I own an Amstaff and I will agree that there is not much difference. The Amstaff I have is quite a bit bigger than the show line Amstaffs of today. He's more the size of the older working lines. I also own a APBT puppy and I can tell you there is so little of a difference between the look, temperment, personality and everything else that it is crazy. You would think they were closely related. They both have to lay with their legs sprawled out behind them and they both love to steal things in our household (ie: cordless drill, couch cushion, 2 X 4, etc)